1. Field of the Invention
The present invention relates to route guidance and an apparatus, method, and computer product thereof.
2. Description of the Related Art
Conventionally, an apparatus that guides a user to a destination such as, for example, a navigation apparatus loaded on a vehicle is known. Such an apparatus can guide the user to the destination using, for example, map information and information on the current location of the vehicle and the destination and by outputting sound and images that indicate a direction for the user to proceed at a traffic intersection (such as turning to the right or left, going straight).
Conventionally, for example, a technique has been known that executes an object monitoring process by obtaining information on the direction of the line of sight of a user identified by a line-of-sight identifying apparatus and an image shot by an object monitoring camera; determining the position of the point viewed by the user in the image; marking the position of the determined vantage point; determining (detecting) a shot object in the marked position as a subject to be monitored; and following and monitoring the subject while moving the marker in correspondence with the movement of the image, which follows the movement of the vehicle (see, for example, Japanese Patent Application Laid-Open Publication No. 2005-251111).
Another known conventional technique, for example, is an apparatus that is loaded on a vehicle and displays various types of information. The apparatus includes a basic display screen that displays various types of information about the vehicle and a unit that displays an image of the environs the vehicle, and enables the driver to recognize the image of the environs of the vehicle when the driver is looking at the main display image (see, for example, Japanese Patent Application Laid-Open Publication No. 2002-277258).
Conventionally, for example, a technique is known that recognizes an object attentively observed by a driver based on an image of the environs of the vehicle and the direction of the line of sight of the driver, estimates a situation of the driver using line of sight distributions that are calculated corresponding to an observation time of the recognized object and a linear identifying function, and presents information to the driver corresponding to the estimated situation of the driver (see, for example, Japanese Patent Application Laid-Open Publication No. 2006-048171).
Conventionally, a variation of the above apparatus is known in which the apparatus outputs, for example, sound and images that provide guidance using detailed information of an arbitrary location on a map. Such an apparatus outputs sound and images that provide guidance by detailed information of a designated location when an operative input manipulation is performed to cause the apparatus to report the detailed information in a state where an arbitrary location on the map is designated.
Conventionally, for example, a technique is known that, when a question by a vehicle operator about an object outside a vehicle is detected, checks the direction of the line of sight of the vehicle operator and an image of the environs the vehicle at a predetermined time period before the time at which the question had been detected, identifies the object, outside the vehicle, that had been in the line of sight of the vehicle operator before the predetermined time period, and obtains and provides information on the identified object (see, for example, Japanese Patent Application Laid-Open Publication No. 2006-090790).
However, with the conventional apparatuses problems have arisen. For example, if the road along which the vehicle is traveling immediately forks after the driver makes a right or left turn in compliance with the sound and image output by the apparatus, the driver may not be able to discern which road to take and may take the wrong road.
As a countermeasure, the frequency of sound and image guidance may be increased, or more detailed guide information may be output, when the vehicle passes through a location where a driver generally tends to take the wrong road. However, an example of a problem that may arise with the countermeasure is that the driver may find the sound and the images output to be too much and bothersome.
The first three conventional techniques described above are techniques to avoid collisions that may occur as a result of the line of sight of the driver being detracted from the road, and are not techniques to indicate whether the route the driver is about to take is correct.
Conventional apparatuses can provide guidance via detailed information of an arbitrary location on a map by executing predetermined operative input commands. However, an example of a problem that may arise is when the driver executes the operative input manipulation while operating the vehicle, which requires the line of sight of the driver to be detracted from the road to the operation terminal, thereby hindering safe vehicle operation.
According to the fourth technique described above, information is provided according to a verbal question. The question is detected by speech recognition processing. An example of a resulting problem is that a question made during a general conversation is also detected as a question posed to the apparatus and excessive information is provided.